North Carolina's Mountain Region
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DAVID S. LEE AND CURTIS SMALLING North Carolina’s Mountain Region he mountain region of North Carolina warmer and dryer period that the region is now experiencing (North American Bird Conservation is one of near maximum deglaciation and has been in Initiative region 28) has many distinctive existence for only about the last 500 years. Thus, bird biotic features resulting from the moist, communities that we consider in the Southeast to be montane cooler climate of high and mid-elevations. are actually relicts from the Pleistocene and recent period, This characteristic of the region has a when they were the dominant species throughout the Tpronounced influence on the region’s bird life, in that many Southeast. While these distinctive features of the North nesting species abound whose centers of distribution are in Carolina mountains are currently linked to species of the New England and Canada. Of particular interest are the boreal and transition forest of northern North America, this endemic taxa that nest in the mountains. An excellent review pattern of distribution is actually very recent. These are in fact of the area’s bird life is provided by M. B. Simpson, Jr. (1992, southeastern species that have invaded the northern portion Birds of the Blue Ridge Mountains , University of North of the continent in the wake of retreating glaciers. The Carolina Press). Piedmont and coastal plain fauna are the recent invaders, with the relict mountain biota giving us a good idea of what the Glaciated climate conditions have predominated in North plant and animal communities were like across the state until America for more than 80 percent of the past 900,000 years. very recent times. During this time, the never-glaciated southeast region of North America, including all of North Carolina, was Geology and Geography occupied by spruce-fir and northern hardwood forest. A tree While a number of southeastern states have portions of the line probably existed at the elevation where spruce-fir now unglaciated southern Appalachians within their political starts. The last tree line and alpine meadow vegetation borders, only in southwestern Virginia and western North disappeared from the South only about 12,000 years ago. The Carolina does this mountain range cover extensive areas and AUDUBON NORTH CAROLINA – IMPORTANT BIRD AREAS OF NORTH CAROLINA | 121 North Carolina’s Mountain Region reach high elevations. This province is based mostly on pre- > Rhododendron-alder: mountain balds has remained stable, both in species composition and relative Cambrian crystalline gneisses and schists and covers about 12 > Red oak: chiefly between 1,219 and 1,524 m (4,000 and dominance of species. The combination of extensive National percent of the state (ca. 15,539 km² [6,000 square miles]), and 5,000 feet) Forests, National Parks, wilderness areas, State Parks, and the all or a significant portion of 17 of North Carolina’s counties. Blue Ridge Parkway provides a mosaic of protected habitats, > American chestnut–black oak: chiefly between 762 and South of the Roanoke River this physiographic province which in turn creates a landscape for a wide variety of 1,524 m (2,500 and 5,000 feet), with chestnut no longer a shifts from a narrow, high ridge to a broad, steep-sided breeding birds. The various land management techniques on dominant tree plateau covered with ridges, knobs, and scattered mountains. these federal lands allows for a continuum of successional > White oak–southern red oak: fertile soils below 914 m Elevations on the plateau generally range from 610 to 762 m communities and ecotonal communities. The parkway (3,000 feet) (2,000 to 2,500 feet), and across the plateau are a series of provides linear and easily accessible habitats for edge and transverse ridges with some of the highest elevations in > River birch–American sycamore: flood plains early-successional species across a wide range of elevations, eastern North America. There are over 200 named mountains > Black willow–alder: stream borders while forestry practices provide extensive areas of early- and that exceed 1,524 m (5,000 feet) and nearly 50 that exceed > Red maple–beech: climax community below 1,676 m midsuccession plant communities in the national forest. 1,829 m (6,000 feet). Mt. Mitchell, at 2,037 m (6,684 feet), is (5,500 feet) on fertile soils. The removal of grazing rights on National Forest land in the the highest point east of the Rocky Mountains. Mean annual > Black jack oak–post oak: sterile soils eastern United States had a dramatic effect on the vegetation temperature drops about two to three degrees for every of most of our forested public lands. For the most part this increase of 305 m (1,000 feet) of elevation. This is Characteristic breeding birds of these forests and ones that are should be viewed as a good decision for conservation, but, accompanied by an increase in precipitation. Thus, 305 m primarily restricted to the mountains at our latitude include compared to lands along the Blue Ridge where grazing (1,000 feet) of elevation is equivalent to about two hundred to Broad-winged Hawk, Ruffed Grouse, Black-billed Cuckoo, continues, it is clear that a number of communities and rare two hundred and fifty miles of similar climatic change in Yellow-bellied Sapsucker, Alder, Willow and Least species, including some birds, benefit from allowing grazing latitude. The average July temperatures for Mt. Mitchell are Flycatchers, Common Raven, Veery, Blue-headed Vireo, on public lands. Old-growth forest and virgin forest occur in 59°F and for January 28°F. The variation in perception is Warbling Vireo, Golden-winged Warbler, Chestnut-sided the parkway are good for observing breeding-season birds, patches in a number of gorges, coves, and wilderness areas. more complex. Higher areas are generally wetter, but areas of Warbler, Black-throated Blue Warbler (also in spruce-fir), and linked to the parkway are a number of the Important While these latter forest types are fragmented, they do fog, condensation, rain, and rain shadow vary, and slope Cerulean Warbler, Swainson’s Warbler, Scarlet Tanager, Bird Areas discussed here (Grandfather Mountain, Mt. provide glimpses into the composition of the precolonial avian exposure results in differential drying. Some areas get as little Rose-breasted Grosbeak, and Vesper Sparrow. Mitchell, Bull Creek, and Chimney Rock, for example). The community. To some degree, where original forest or old- as 102 cm (40 inches) of precipitation. These climatic parkway terminates near the entrance for the Smoky Within these forests are several subcommunities that are growth forests persist, species that are now regarded as high- conditions result in avifauna that contrast sharply from what Mountain National Park. For people not familiar with the important to various assemblages of mountain birds. These elevation specialists occur in densities that are similar to what is found in the Piedmont and coastal plain regions of the region, traveling the length of the parkway with side include hemlock stands, cove hardwoods, and mountain bogs. they are in high-elevation spruce-fir forests. This suggests that southeast, with considerable variation within the province. excursions to various Important Bird Areas would provide an In many cases these communities support fauna that are more prior to logging these species had much broader distributions The Appalachians is one of the oldest mountain ranges on excellent introduction to the region’s biotic communities and characteristic of those found at higher elevations. and occurred in a wider variety of habitats than they do today, earth and the actual topography of the region has not changed bird life. From a bird-watching perspective, this route is not with many “high-elevation” species breeding as low at 610 m since early Pleistocene (although a number of the river Boreal Forest: recommended during the fall because of the large number of Boreal spruce-fir forests are found above 1,524 (2,000 feet) in old-growth communities. systems in existence today flow differently than they did even m (5,000 feet) on cold mountain summits in the extreme parkway visitors coming to see fall colors. The only habitats 15,000 years ago). western portion of the state. The characteristic flora consist of not represented in this 241-mile north-to-south transect (the Historically and presently most of the land clearing has been Birds and Habitats Fraser’s fir, red spruce, mountain ash, mountain rosebay, and a North Carolina stretch) are the ancient-growth forest of Joyce in mountain valleys. Here, open areas cleared for agriculture, Kilmer and some of the mountain valley habitats, best golf courses, and similar uses provide habitat for a number of The mountain region supports two major upland dense, damp ground cover dominated by mountain fern moss represented by the New River Flood Plain. species that would not be expected in the region. The clearing communities, but these communities vary considerably in soil and common wood sorrel. of land and subsequent succession, which is often held in type, moisture, exposure, and the timing and extent of human The 19 Important Bird Areas in the mountain region contain Characteristic breeding birds which at our latitude are species check by current land use, has allowed at least 20 breeding disturbance. The transition zones between these forest types representative habitats of all the key natural communities of restricted to the mountains include Northern Saw-whet Owl, species to invade the region. These are all species that were are normally narrow. the region. They also support breeding populations of all the Olive-sided Flycatcher, Black-capped Chickadee, Red- not present 100 years ago. At the same time only seven species indigenous to the region, with a concentration among Upland Mesophytic Forest: Various seral stages of the middle- breasted Nuthatch, Brown Creeper, Winter Wren, Golden- montane species have exhibited declines in their current high-elevation communities.